World War I (1914–1918) and World War II (1939–1945)

Introduction
World War I (1914–1918) and World War II (1939–1945) were two of the most devastating
conflicts in modern history, reshaping global power structures and leaving deep political,
economic, and social impacts. World War I was primarily sparked by the assassination of
Archduke Franz Ferdinand, but underlying causes included nationalism, imperial rivalries,
militarism, and a complex alliance system. The Treaty of Versailles, which ended WWI,
imposed harsh penalties on Germany, sowing the seeds of resentment that fueled the rise of
Adolf Hitler and the Nazi Party. World War II emerged from this volatile postwar environment,
driven by fascist expansionism, economic instability, and the failure of collective security. It
became a truly global conflict, involving vast military campaigns across Europe, Asia, and
Africa. Both wars significantly altered international relations, led to the collapse of empires,
and set the stage for the Cold War, the United Nations, and a new world order based on
diplomacy, deterrence, and reconstruction.

First World War (1914-1918): Causes and Consequences

The First World War (World War I) is considered as one of the largest wars in history. The
world’s great powers assembled in two opposing alliances: the Allies (British Empire, France
and the Russian Empire) versus the Central Powers (Germany and Austria-Hungary). WWI
lasted from 28 July 1914 to 11 November 1918
The Two Groups: Allies vs Central Powers
Causes of the First World War
In the background there were many conflicts between European nations. Nations grouped
among themselves to form military alliances as there were tension and suspicion among them.
The causes of the First World War were:
(1) Conflict between Imperialist countries: Ambition of Germany
● Conflict between old imperialist countries (Eg: Britain and France) vs new imperialist
countries (Eg: Germany).
● Germany ship – Imperator.
● German railway line – from Berlin to Baghdad.
(2) Ultra Nationalism
● Pan Slav movement – Russian, Polish, Czhech, Serb, Bulgaria and Greek.
● Pan German movement.
(3) Military Alliance
● Triple Alliance or Central Powers (1882) – Germany, Italy, Austria-Hungary.
● Triple Entente or Allies (1907) – Britain, France, Russia.
Note: Although Italy was a member of the Triple Alliance alongside Germany and Austria-
Hungary, it did not join the Central Powers, as Austria-Hungary had taken the offensive,
against the terms of the alliance. These alliances were reorganised and expanded as more
nations entered the war: Italy, Japan and the United States joined the Allies, while the Ottoman
Empire and Bulgaria joined the Central Powers.
(4) International Anarchy
● Secret agreement between Britain and France allowing Britain to control Egypt and France
to take over Morocco. Germany opposed, but settled with a part of French Congo.
● Hague conference of 1882 and 1907 failed to emerge as an international organisation.
(5) Balkan Wars
● Many Balkan nations (Serbia, Bulgaria, Albania, Greece and Montenegro) were under the
control of Turkey. They defeated Turkey in the First Balkan War. The subsequent war was
between the Balkan countries themselves – Eg: Serbia vs Bulgaria.
● Defeated countries like Turkey and Bulgaria sought German help.
(6) Alsace-Loraine
● During German unification, Germany got Alsace-Loraine from France. France wanted to
capture Alsace-Loraine back from Germany.
(7) Immediate Cause: assassination of Francis Ferdinand
● Austrian Archduke Francis Ferdinand was assassinated by a Serbian native (in Bosnia).
Austria declared war on Serbia on 28th July, 1914. [Reason for assassination: Annexation by
Austria the Bosnia-Herzegovina, against the congress of Berlin, 1878]

The Course of the War

● Group 1 (Allies): Serbia, Russia, Britian, France, USA, Belgium, Portugal, Romania etc
● Group 2 (Central Powers): Austria-Hungary, Germany, Italy, Turkey, Bulgaria etc.
● War on Western Side: Battle of Marne.
● War on Eastern Side: Battle of Tennenberg (Russia was defeated).
● War on the Sea: Batter of Dogger Bank (Germany was defeated), Battle of Jutland (Germany
retreated).
● USA entered in 1917.
● Russia withdrew in 1917 after October Revolution.
Treaty of Versailles, Paris
● Germany signed a treaty with Allies (Triple Entente) on 28th June 1919. It was signed at
Versailles, near Paris. (14 points)
● Leaders: Clemenceau – France, Lloyd George – Britain, Woodrow Wilson – USA, Orlando
– Italy. Treaties after Wor

Consequences of First World War

1. Rule of King ended in Germany: Germany became a republic on November 1918. The
German Emperor Kaiser William II fled to Holland.
2. Around 1 crore people were killed.
3. Unemployment and famine.
4. Epidemics.
5. The fall of Russian empire after October revolution (1917) which resulted in the formation
of USSR (1922)
6. Emergence of USA as a super power.
7. Beginning of the end of European supremacy.
8. Japan became a powerful country in Asia.
9. Poland, Yugoslavia and Czechoslovakia became new independent states.
10. Baltic countries – Estonia, Latvia and Lithvania – became independent.
11. Rule of Ottamans came to an end in Turkey.
12. New boundary lines were drawn for Austria, Germany and Turkey.
13. Strengthened independence movements in Asia and Africa.
14. League of Nations came into being.
15. Germany had to return Alsace-Loraine to France.
16. German colonies were shared.
17. Germany gave up Saar coal field.
18. Germany gave up Polish corridor, and made city of Danzig independent.
19. Monarchy was abolished in Germany, Austria, Hungary, Turkey and Russia.
20. The harsh clauses of the Treaty of Versailles finally resulted in the second world war
Second World War
We have seen the causes and consequences of the First World War in the last post. The First
World War itself sowed the seeds for the Second World War, primarily because of the
humiliating Treaty of Versailles. We shall see the causes and consequences of the Second
World War (WWII) in this post. The Second World War fundamentally reshaped the global
order, setting the stage for the Cold War and dramatically altering the political, social, and
economic landscapes of the 20th century.
Causes of Second World War(1939-1945)
(1) Humiliation by the Treaty of Versailles
The harsh terms imposed on Germany by the Treaty of Versailles, including significant
territorial losses, reparations, and military restrictions, led to widespread resentment in
Germany. This environment of humiliation and economic hardship paved the way for the rise
of Adolf Hitler and the Nazi Party, who promised to restore Germany’s former glory.
● War indemnity.
● The provision for disarming Germany.
● Saar coal mine to France for 15 years.
● Polish corridor was given to Poland.
● City of Danzing was made free.
(2) Growth of Fascism and Nazism
The interwar period saw the rise of fascist and totalitarian regimes in countries like Italy,
Germany, and Japan. Leaders such as Benito Mussolini, Adolf Hitler, and the militaristic
government of Japan pursued aggressive expansionist policies, seeking to overturn the post-
World War I international order and establish dominance.
● Mussolini (Italy) and Hitler (Germany) strongly glorified war and violence.
● While the West was fighting communism, Germany and Italy started massive militarization.
(3) Rise of Japan
The League of Nations, established to maintain peace, was ineffective in preventing
aggression by fascist powers. Its inability to enforce collective security, particularly in
response to Japanese aggression in Manchuria (1931), the Italian invasion of Ethiopia (1935),
and German reoccupation of the Rhineland (1936), emboldened these p
● Imperialism.
● Rome-Berlin-Tokyo axis (1936).
(4) Neglect of minority interests
European powers, particularly Britain and France, pursued a policy of appeasement in the
1930s, allowing Hitler to annex Austria (Anschluss, 1938) and the Sudetenland (Munich
Agreement, 1938) without significant opposition. This emboldened Hitler to continue his
expansionist agenda, ultimately leading to the invasion of Poland.
● New countries like Poland, Czechoslovakia and Austria were formed after the First World
War. While drawing boundaries the interests of minority groups in each of these countries
were neglected.
(5) Military Alliance
● Allies – Britain, France, USA, USSR and China vs Axis Powers – Germany, Italy and Japan
● Leaders – Churchill (Britain), Roosevelt (USA), Stalin (USSR)
(6) Germany’s attack on Czechoslovakia
● Despite the Munich Pact between Germany and Britain (1938), Germany re-attacked and
sized Czechoslovakia.
(7) Immediate Cause: Germany’s invasion of Poland (1st September 1939)
● Germany annexed the Polish Corridor and Danzig city. The sudden attack on Poland is
known as Blitzkrieg (lightning war).
● Britain and France declared war on Germany.

The course of the War

● World War II officially began on September 1, 1939.
● Germany conquered – Poland, Norway, Denmark, Belgium, Holland and France.
● Battle of Britain – Germany vs Britain (air battle; German Air Force =Luftwaffe).
● Battle of Stalingrad – Germany vs USSR. (Operation of Barbarossa (1941 = Attack on
Yugoslavia and Greece; Russia countered the attack on Moscow with Scorched Earth Policy)
● Atlantic Charter (August 1941) – Between Churchill (UK) and Roosevelt (USA).
● Pearl Harbor Attack (7th December 1941) – Japan on USA.
● Italy vs UK in Africa (1942) – Ethiopia, Kenya, Sudan, British Somaliland, Eritrea.
● France was conquered by Germany in 1940, but British and American troops liberated
France in 1944.
● Atom bomb – Hiroshima and Nagasaki.

Consequences of Second World War

● Human and Economic Cost: World War II was the deadliest conflict in human history,
resulting in an estimated 70-85 million deaths, including civilians and military personnel. The
war caused widespread destruction, particularly in Europe and Asia, leading to massive
economic and infrastructure devastation.
● Redrawing of National Borders: The war led to significant changes in national borders,
especially in Europe. Germany was divided into four occupation zones controlled by the Allies
(the U.S., the UK, France, and the Soviet Union), eventually leading to the creation of West
Germany and East Germany.
● Rise of the United States and the Soviet Union as Superpowers: The United States and the
Soviet Union emerged as the two dominant superpowers in the post-war world, leading to the
Cold War. Their ideological conflict between capitalism and communism shaped global
politics for the next several decades.
● Decolonization: The war weakened the colonial powers, particularly Britain and France,
leading to a wave of decolonization in Asia, Africa, and the Middle East. Countries like India,
Indonesia, and numerous African nations gained independence in the years following the war.
● Creation of the United Nations: In response to the failure of the League of Nations and the
devastation of World War II, the United Nations was established in 1945 to promote
international cooperation and prevent future conflicts. The UN played a central role in shaping
the post-war international order.
● Cold War and Division of Europe: The ideological and political rivalry between the United
States and the Soviet Union led to the division of Europe, with Eastern Europe falling under
Soviet influence and Western Europe aligning with the United States. This division was
symbolized by the Iron Curtain and culminated in the fall of the Berlin Wall (1961-1989).
● Holocaust and Genocide Awareness: The Holocaust, in which six million Jews were
murdered by Nazi Germany, highlighted the horrors of genocide. This led to increased global
awareness of human rights and the establishment of conventions against genocide and crimes
against humanity.
● Nuclear Arms Race: The use of atomic bombs by the United States on Hiroshima and
Nagasaki in 1945 introduced nuclear weapons to the world, leading to an arms race during the
Cold War. The threat of nuclear warfare became a central issue in international relations.

Conclusion
World War I and World War II collectively reshaped the 20th century, highlighting the
catastrophic costs of militarism, nationalism, and unchecked political aggression. While World
War I ended with unresolved tensions, World War II concluded with clearer efforts at
rebuilding and international cooperation. These wars not only redrew global borders but also
triggered technological advancements, decolonization, and new political ideologies. Most
importantly, they taught the world vital lessons about the importance of peace, diplomacy, and
human rights. The legacy of both conflicts continues to influence global politics, security
strategies, and efforts to prevent future large-scale wars.